1. Field of the Invention
This invention relates to hydraulic coupling members. More particularly, it relates to seals used to seal between the probe of a male subsea hydraulic coupling member and the body of a female subsea hydraulic coupling member.
2. Description of the Related Art Including Information Disclosed Under 37 CFR 1.97 and 1.98.
A wide variety of hydraulic coupling members are known in the art. Typically, a coupling is comprised of two members—a male member having a generally cylindrical probe and a female member having a receiving chamber equipped with one or more seals for providing a fluid-tight seal with the outer surface of the probe element of the male member.
For high-temperature, high-pressure applications, a probe seal having a dovetail interlocking fit with the body of a female coupling member has proven to be a particularly effective configuration. In certain coupling members, the probe seal has a dovetail interlocking fit with a seal retainer or seal cartridge in the female coupling member.
U.S. Pat. Nos. 5,099,882 and 5,203,374 disclose a pressure balanced hydraulic coupling with a variety of seals having a dovetail interlocking fit that prevents radial movement of the seal into the bore. This pressure balanced coupling has radial passageways communicating between the male and female members such that substantial fluid pressure is not exerted against the face of either member during coupling or uncoupling or during the coupled state. Radial passageways in the male and female members match up at their longitudinal surfaces so that fluid pressure between the male and female members is in a substantially radial direction and is not exerted at the face of either member. A first pair of seals is positioned on each side of the radial passage for sealing between the receiving chamber and the seal retainer. A second pair of seals is positioned on each side of the radial passage for sealing between the seal retainer and the male member.
U.S. Pat. No. 5,390,702 discloses an undersea hydraulic coupling having a male member with a stepped outer body that is inserted into a female member having a bore with stepped internal cylindrical surface. The step in the male member defines first and second external cylindrical surfaces which are slidably received in the female member bore and in a sleeve member before the seals, which are retained by the sleeve member, engage the male member. Thus, the male member is more accurately positioned and guided into the seals, insuring greater seal reliability and longer seal life. The stepped surfaces also help prevent implosion of the seals due to sea pressure when the end of the male member comes out of the seals.
U.S. Pat. No. 6,123,103 discloses another pressure balanced hydraulic coupling for use in undersea drilling and production operations which is equipped with dovetail type seals. The female member has a split body with a first part and a second part, each having a longitudinal passage and a radial fluid passage. A radial seal is positioned on the junction between the first and second parts of the female member body to facilitate removal and replacement of the radial seal when the split body is disassembled. The male member may be inserted through the first and second parts of the female coupling member, thereby establishing fluid communication between the coupling members in a direction transverse to the coupling member bores.
U.S. Pat. No. 6,206,040 discloses another undersea hydraulic coupling with seals having a dovetail profile. This undersea hydraulic coupling has a stepped internal bore dimensioned to increase the flow rate through the coupling. The coupling allows an increased flow rate without increasing the size or weight of the coupling by positioning the poppet valve in the body section, rather than in the probe section, of the male coupling member.
U.S. Pat. No. 6,575,430 discloses an undersea hydraulic coupling member having a ring-shaped seal with multiple sealing surfaces that extend inwardly from the inner surface in a radial direction. The multiple sealing surfaces help guide the probe of the male coupling member into the female member without the risk of drag or galling of the receiving chamber or metal seal retained therein. The seal has reverse inclined shoulders which provide an interlocking fit in the female member to restrain the seal from moving radially inwardly due to vacuum or low pressure in the receiving chamber. One particular embodiment of the ring-shaped seal includes a third radial sealing surface that may be pressure energized by hydraulic fluid pressure in the coupling to enhance the radial seal with the probe of the male coupling. As hydraulic fluid at high pressure enters a cavity, the third sealing surface is urged in an inward, radial direction against the outer surface of the male probe.
U.S. Pat. No. 4,190,259 describes a single apex, two element, fluid pressure seal assembly that has a convergingly tapered surface defining a central vertex or apex that projects radially from the seal body. The vertex creates a narrow contact dynamic seal area between the apex and the surface of an adjacent machined part. Seals of this type are available from Microdot Manufacturing, Inc. (Salt Lake City, Utah 84120) under the CROWN SEAL® brand name.
U.S. Pat. No. 6,179,002 describes an undersea hydraulic coupling with a pressure-energized dovetail seal. The seal has a pair of flexible sealing surfaces for sealing with the male and female coupling members, and a cavity therebetween that is exposed to fluid pressure in the coupling. The outer circumference of the seal has a dovetail interfit between inclined shoulders in the female member bore and on a seal retainer that holds the seal in the bore.
U.S. Pat. Nos. 5,052,439 and 4,900,071 describe an undersea hydraulic coupling which includes a male member and female member, and a two-piece retainer for restraining radial movement of a wedge-shaped annular seal into the central bore of the female member. The two-piece retainer includes a cylindrical retainer sleeve member slidably received within the female member bore, and a threaded retainer-locking member threadable to mating threads in the wall of the central bore. The retainer-locking member holds the retainer sleeve member in place within the female member bore. The annular seal is restrained from radial movement by a dovetail interlocking fit with a mating shoulder on at least one of the retainer sleeve and the retainer-locking members.
U.S. Patent Publication Nos. 2009/0273144 A1 and 2009/0273181 A1 disclose probe seals for a female hydraulic coupling member that have one or more circumferential pressure-energized seals for sealing between the probe seal and the body of the coupling member. An annular cavity in the side wall of the probe seal is open to the outer cylindrical surface of the generally ring-shaped probe seal. Hydraulic fluid, under pressure, can enter the annular cavity through the opening and exert a radial force on sealing elements. In certain embodiments, the annular cavity is generally L-shaped in cross section; in other embodiments, the annular cavity is generally T-shaped in cross section. In some embodiments, a pressure differential also imparts an inwardly-directed radial force to the crown seal.